Add some more debugging info so we can determine why this test is flaking

test/e2e/kubectl.go

@@ -788,6 +788,7 @@ func waitForGuestbookResponse(c *client.Client, cmd, arg, expectedResponse strin
 		if err == nil && res == expectedResponse {
 			return true
 		}
+		Logf("Failed to get response from guestbook. err: %v, response: %s", err, res)
 	}
 	return false
 }